Gasoline composition



United States Patent 3,091,521 GASOLINE COMPOSITION Chien' wei Liao, Beachwood, Ohio, assignor to The Stand- Oil Company, Cleveland, Ohio, a corporation of 10 No Drawing. Filed- May 3, 1960, Ser. No. 26,437 2 Claims. (Cl. 44-456) The present invention relates to an improved gasoline composition. More particularly, the present invention relates to a gasoline for a spark-ignited internal combustion engine which is effective in minimizing the formation of carburetor deposits, thereby promoting improved engine operation.

It is well known that harmful deposits accumulate in the carburetors of motor vehicles from contaminated intake air which the carburetor must breathe in by tremendous volumes for engine operation. This condition is experienced in particular by cars which are operated in urban areas. The major contributor to this responsible contamination in the air is believed to be the combustion products exhausted from the large population of other cars operating in the same immediate area. The condition is, of course, aggravated by any blowby fumes from the operation of the cars own engine or by any other under-hood fumes generated by the cars engine, in addition to any industrial fumes present in the air which the carburetor breathes. These sources of contamination are cumulative and may cause the rapid buildup of deposits on the carburetor of the engine.

Such deposits manifest themselves by causing rough idling of the engine and in many cases the occurrence of frequent stalling. Although the motor fuel itself isnot responsible for these effects, it ofi'ers the most likely agency for introducing a material which may serve as a remedy for such an undesirable condition.

It therefore is the aim of this invention to provide a fuel containing an additive compound which is effective in significantly minimizing the deposits which form in the carburetor of an internal combustion engine during continued operation. It has been found that this aim may be accomplished by incorporating in the gasoline an additive compound of the following general formula:

wherein R is selected from a group consisting of alkyl, alkenyl, or alicyclic radicals containing from 7 to 21 carbon atoms and R is an alkyl group containing up to 5 carbon atoms. The mono-oleated ester of triethanol amine and the mono-oleated ester of tri-isoprop-anol amine are particularly desirable for purposes of the present invention.

The amount of additive compound that is to be added to the gasoline may vary. Generally, the smallest amount that will give significant results will be in the order of 0.001% by weight. Usually amounts greater than approximately l% by weight cannot be justified economically. A preferred range for purposes of the present invention is from about 0.005% to 0.1% by weight.

The gasoline base stocks to which these compounds are added may be any of those conventionally used in prep-aring a motor gasoline for a spark-ignited internal combustion engine, such as catalytic distillate, motor polymer, alkylate, catalytic reformate, isomerate, naphthas, etc. The motor fuel may also contain tetraethyl lead in amounts of from /2 ml. per gallon to 6 ml., but preferably 3 ml. per gallon, and a scavenging agent. In addition, the gasoline may contain other common additives such as antioxidants, stabilizers, solvent oils, dyes, and the like.

3,091,521 Patented May 28, 1963 The mouo-acylated trialkanol amine compounds are preferably prepared by reacting the desired trialkanol amine compound with a fatty acid or a naphthenic acid compound containing from 8 to 22 carbon atoms in an equimolar relationship. A preparation of the mono-cleated ester of triethanol amine is typical and is as follows:

113 grams of oleic acid and 59.6 grams of triethanol amine (a 1:1 molar relationship) were mixed in a flask together with 200 ml. of toluene. The reaction mixture was heated with stirring at the azeotropic distillation temperature until one mole of water of reaction was removed overhead in an azeotrope trap for each mole of oleic acid and triethanol amine reacting. The reaction product was filtered and the excess solvent removed by distillation. The product was a clear" viscous liquid at room temperature which was soluble in gasoline.

It is to beundersto'od that any saturated or unsaturated fatty acid of about 8 to 22 carbon atoms may be substituted for the oleic' acid in the above preparation. It follows that mixtures of fatty acids may be used and this will commonly be the case since it is preferable economically to use commercially avail-able fatty acids derived from tallow and naturally occurring oils, such as cottonseed oil, soybean oil, coconut oil, tall oil, and the like, and hence R in the foregoing general formula will corresporid principally to the fatty acid radicals present in such fats and oils. The R radical may also be suitably derived from naphthenic acids containing from 8 to 22 carbon atoms.

To offer a clearer understanding of the benefits derived by the use of these compounds in gasoline, the following test was conducted employing a contamination system deyised to simulate the conditions which contribute to carbure'tor deposits in the operation of motor vehicles in urban areas. The system comprises the operation of a slave engine and a test engine. The exhaust gases from one bank of the slave engine (4 cylinders) is metered to the crankcase of the test engine at a rate of 1.5 cubic feet per minute. All gases in the crankcase of the test engine are passed to the air intake of the carburetor of the test engine, including, therefore, the exhaust gases from the slave engine and the blowby fumes of the test engine. The 1.5 cubic feet per minute rate of exhaust gases from the slave engine under these conditions constitutes approximately 8% of the total air intake of the test engine at idle manifold, vacuum and speed. The operating conditions for the two engines are as follows:

The test cycle was 2 hours in time, which included four acceleration periods conducted on the unloaded test engine spaced at /2 hour intervals, the first acceleration period being 30 minutes after the test cycle was commenced. During each acceleration period the throttle was moved quickly to a wide open position and then quickly closed again to an idle position five separate times to permit a surge of carburetted gasoline to come into contact with the carburetor parts. The carburetor at the start of each test was in spotless condition. All experimental conditions were the same for the two test cycles except for the gasoline.

The base fuel in each test was the same and had the following composition and specifications:

At the end of each test the carburetor was removed and disassembled and a numerical rating was assigned for amount of deposits and discoloration by a number of observers rating independently and uninformed of the gasoline they were rating. The rating assigned was based on a standardized scale ranging from 100 to 0, wherein 100 would be a rating of a perfectly clean carburetor throttle plate and barrel, and 0 rating would represent a throttle plate and barrel loaded with deposits.

The results below represent the average rating by the observers.

Additive: Rating None 28 Mono-oleated ester of triethanol amine at 0.005%

by weight 50 It will be obvious from the above data that only small amounts of the additive compound of the present invention are required to significantly improve the rating of the gasoline with respect to carburetor cleanliness.

It is to be understood that various modifications of the present invention will occur to those skilled in the art upon reading the above description. All such modifications are intended to be included as may be reasonably covered by the appended claims.

I claim:

1. A gasoline for minimizing carburetor deposits containing a deposit minimizing amount within the range of 0.001 to 1.0 weight percent of a compound selected from the formula:

wherein R represents a radical selected from the group consisting of alkyl, alkenyl and alicyclic radicals containing from 7 to 21 carbon atoms and R is an alkyl radical containing up to 5 carbon atoms.

2. A gasoline for minimizing carburetor deposits containing the mono-oleated ester of triethanol amine in a deposit minimizing amount within the range of 0.001% to 1.0% by weight of gasoline.

References Cited in the file of this patent UNITED STATES PATENTS Re. 21,530 Kritchevsky Aug. 13, 1940 1,990,365 Beale Feb. 5, 1935 2,110,274 Mikeska et a1 Mar. 8, 1938 2,125,448 Johnson et al Aug. 2, 1938 2,862,800 Cantrell et al Dec. 2, 1958 2,922,707 Lindstrom et al Jan. 26, 1960 3,011,879 Buckmann et al Dec. 5, 1961 OTHER REFERENCES Emulsions, Carbide and Carbon Chemicals Corp.-,

Seventh Edition, April 15, 1946. Received in Library April 1, 1947, page 13. 

1. A GASOLINE FOR MAINIMIZING CARBURETOR DEPOSITS CONTAINING A DEPOSIT MINIMIZING AMOUNT WITHIN THE RANGE OF 0.001 TO 1.0 WEIGHT PERCENT OF A COMPOUND SELECTED FROM THE FORMULA: 